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Question

Let Q = x² + bx + c. If the sum of the roots is equal to product of the roots of the equation Q = 0, then which of the following statements is/are correct ?
I. Q can be a perfect square.
II. Q is positive for all real values of x.
Select the answer using the code given below :

This question was previously asked in
CDS 2 2026 Maths Question Paper (13-Sep-2026)
The correct answer is
I only

To solve the given problem, we need to analyze the equation \( Q = x^2 + bx + c \) under the condition that the sum of the roots is equal to the product of the roots.

We know that for a quadratic equation \( ax^2 + bx + c = 0 \) (in this case, \( a = 1 \) for \( x^2 + bx + c = 0 \)), the sum of the roots \( \alpha + \beta \) is given by \( -\frac{b}{a} \), and the product of the roots \( \alpha \beta \) is \(\frac{c}{a}\).

Given:

The sum of the roots = Product of the roots.

\(-\frac{b}{1} = \frac{c}{1}\)

This simplifies to:

\(b = -c\)

Now, let's analyze each statement:

  1. Statement I: Q can be a perfect square.
  2. Statement II: Q is positive for all real values of x.

Therefore, the correct choice is I only.

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